The anti-vaccination movement is a loosely-organized conspiracy theorist subculture that blames the medical practice of vaccinations for a wide range of health problems. The movement, to a large majority led by people with no medical or scientific qualifications (or, ironically, stripped of credentials for malpractice and fraud), is based largely on spuriously alleged short- and long-term side effects of vaccinations. Effects which are — to boot — often trivial when compared to the severity of what were once common illnesses.

Scaremongering opposition to vaccines is antiquated rather than novel, however, and the iteration of this movement that we're stuck with today is not responding to any current, new (or real) danger. The original anti-vaccination movement sprang up very soon after the first vaccine had been invented by Edward Jenner in 1798. "Vacca," being Latin for "cow," is what gave the new invention, the vaccine, its name, and as early as in 1802, just four years later, forerunners to the modern anti-vaccination movement literally claimed that getting the smallpox inoculation would turn you into a cow.[3] While vaccines have since improved from Jenner's primitive proof-of-concept to the modern medical science we reap the benefits of today, the anti-vaccination movement hasn't smartened up noticeably from the level held by their predecessors in the days of Jenner.

In recent times, there has been much debate in the press and in the doctor's office regarding what possible side effects vaccines cause and whether these outweigh the risks of leaving a population without a vaccination schedule. Vaccines have been alleged to cause all manner of illnesses; autism is a prominent example, as its direct causes are still fairly mysterious and probably very wide-ranging, with no single cause or lifestyle risk factor being identified. Some prominent Americans have also spoken out vociferously about the supposed danger of vaccines.[4]

The mechanisms for claimed health problems are rejected or have not been explained by current scientific research. Vaccine-preventable diseases have been a major cause of illness, death, and disability throughout human history. The advent of the modern vaccine era has changed this significantly; most North Americans and Europeans have little memory of a pre-vaccine era where diseases such as mumps and measles - to say nothing of smallpox or polio - were common and often deadly.

In the United States, many state laws support an individual (or parental) right to choose whether to be vaccinated against any disease. Forty-eight states allow religious exemptions for compulsory vaccinations as of 2014, and twenty states allow exemptions on philosophical or personal objections to vaccinations.[5]

John D. Grabenstein wrote an extensive analysis on parents' religious exemptions for vaccines versus what a wide range of religions actually say. His analysis found that there were "few canonical bases for declining immunization, with Christian Scientists a notable exception." Parents' claims for religious exemption were usually based on irrational fears rather than specific religious tenets.[6][7]

“”There's a small, but still sizable group of people who are choosing not to vaccinate their children. Here in LA, there are schools in which 20% of the students aren't vaccinated, because parents here are more scared of gluten than they are of smallpox! And, as a result, we now have measles again.

I know if you're one of these anti-vaccine people you probably aren't going to take medical advice from talkshow hosts — I don't expect you to, I wouldn't either — but I would expect you to take medical advice from almost every doctor in the world. See, the thing about doctors is they didn't learn about the human body from their friend's Facebook page. They went to medical school, where they studied all sorts of amazing things, like how to magically prevent children from contracting horrible diseases by giving them little shots. You know these little shots of Botox? Which is Botulinum toxin, by the way? You get in your face to make your head look smooth and your eyes look crazy? A little shot, like that, and "poof!" — polio is gone.

But some people did not buy into that, because they did a Google search, and Jenny McCarthy popped up. And she had clothes on, so they listened to what she had to say, and decided not to vaccinate their kids. And by the way, this would all be OK if your kids were the only ones affected — they're your kids. But they're not, because unvaccinated kids put all children in danger, especially babies who are too young to get the vaccination shot... But of course, that's according to doctors, so - you know, take that with a grain of salt.

There are many ideas which are not supported by reviewed and accepted scientific evidence that vaccines are inherently harmful. For example, it is claimed that specific vaccines such as MMR (mumps, measles and rubella), or specific ingredients like thiomersal are causative factors leading to disease. Some claims are more vague, based on the feeling that vaccines are "unnatural," that they are somehow "useless," or that the diseases they prevent "aren't that bad anyway." Anti-vaccination campaigners often use the language of being for "freedom" in whether to be vaccinated, such as with MMR, where the campaign was the "choice" to take a non-combined vaccine. These beliefs often stem from other ideological positions; for instance, vaccination programs are seen as excessive government interference, or as an implementation of socialized medicine, although it's hardly just a conservative thing, as a look around The Huffington Post will tell you, and New Agewoo is another reason some oppose vaccines. Similarly, those against "artificial" interference will also shun vaccination regardless of efficacy. It could be argued that these ideologies are the root causes of anti-vaccination positions, and bias which specific concern an individual will be attracted to.

There are, of course, well developed published data on the complication rates of vaccines and these data play an essential role in the approval process vaccines must pass in order to be licensed for sale, and recommended for use.[9] When faced with this, anti-vaccination activists often argue that the reporting system is not robust enough, resulting in these figures being misleading. The reality is that unexpected side effects can occur, just as a parachute may fail to open, but the regulatory process ensures that such events are rare and within a risk boundary that means vaccination is statistically much safer than non-vaccination.

For vaccination recommendations by governments or advisory institutions (e.g. the World Heath Organization) to change to an anti-vaccination stance, it must be fully demonstrated that the harms caused directly by the vaccine are greater than the harms caused by withholding the vaccine from circulation. This needs to be demonstrated at a population level, with solid and significant statistics.

A major cause of confusion among anti-vaxxers is the utter lack of understanding of the difference between actual research and woo that someone wrote on their blog. Having little to no understanding of science or the scientific process, a parent is all too often more likely to trust something that entertains them even while it scares them. While this is no doubt also propagated by the media, there is a key element of human behavior at play here as well. Much of the anti-vaccine movement's successes lie more with how they present their "arguments" rather than what they're actually saying.

For example, if a television network were to create an anti-vaccine special in which they used a deep-voiced narrator, ominous music, and anecdotal cases of autism that fail to provide a causal link to vaccines, parents' minds would likely be swayed long before they cut to a commercial break following the narrator saying, "Find out what happens next when Billy gets his shot. You won't be able to believe your eyes. All this and more when we return to Vaccines: the deadly poison."

And to top it all off — even though a stream of new scientific studies have kept confirming that the fears of the anti-vaccination movement are completely unfounded, these conclusions are not reaching the anti-vaxxers. Instead, the very existence of new safety studies is paraded by the anti-vaxxers as an implicit concession that the safety of vaccines must clearly be insufficiently proven — even though the safety trials were only re-done in the first place order to appease the constantly goalpost-moving anti-vaccination movement.[13] Against this kind of stupidity, the gods themselves contend in vain.

The anti-vaccination movement also contains a significant religious element. The damage done to the lives of innocent human beings, especially the poorest and hardest stricken, by this anti-scientific movement is both remarkable and heartbreaking. As related by the late Christopher Hitchens:[15]

In the fall of 2001 I was in Calcutta with the magnificent photographer Sebastião Salgado, a Brazilian genius whose studies with the camera have made vivid the lives of migrants, war victims, and those workers who toil to extract primary products from mines and quarries and forests. On this occasion, he was acting as an envoy of UNICEF and promoting his cause as a crusader — in the positive sense of that term — against the scourge of polio. Thanks to the work of inspired and enlightened scientists like Jonas Salk, it is now possible to immunize children against this ghastly malady for a negligible cost: the few cents or pennies that it takes to administer two drops of oral vaccine to the mouth of an infant.

Advances in medicine had managed to put the fear of smallpox behind us, and it was confidently expected that another year would do the same for polio. Humanity itself had seemingly united on this proposition. In several countries, including El Salvador, warring combatants had proclaimed cease-fires in order to allow the inoculation teams to move freely. Extremely poor and backward countries had mustered the resources to get the good news to every village: no more children need be killed, or made useless and miserable, by this hideous disease.

Back home in Washington, where that year many people were still fearfully staying indoors after the trauma of 9/11, my youngest daughter was going dauntlessly door to door on Halloween, piping "Trick or Treat for UNICEF" and healing or saving, with every fistful of small change, children she would never meet. One had that rare sense of participating in an entirely positive enterprise.

The people of Bengal, and particularly the women, were enthusiastic and inventive. I remember one committee meeting, where staunch Calcutta hostesses planned without embarrassment to team up with the city's prostitutes to spread the word into the farthest corners of society. Bring your children, no questions asked, and let them swallow the two drops of fluid. Someone knew of an elephant a few miles out of town that might be hired to lead a publicity parade. Everything was going well: in one of the poorest cities and states of the world there was to be a new start.

I wondered as I left Calcutta if West Bengal would manage to meet the deadline and declare itself polio-free by the end of the next year. That would leave only pockets of Afghanistan and one or two other inaccessible regions, already devastated by religious fervor, before we could say that another ancient tyranny of illness had been decisively overthrown.

In 2005 I learned of one outcome. In northern Nigeria — a country that had previously checked in as provisionally polio-free — a group of Islamic religious figures issued a ruling, or fatwa, that declared the polio vaccine to be a conspiracy by the United States (and, amazingly, the United Nations) against the Muslim faith. The drops were designed, said these mullahs, to sterilize the true believers. Their intention and effect was genocidal. Nobody was to swallow them, or administer them to infants.

Within months, polio was back, and not just in northern Nigeria. Nigerian travelers and pilgrims had already taken it as far as Mecca, and spread it back to several other polio-free countries, including three African ones and also faraway Yemen. The entire boulder would have to be rolled back right up to the top of the mountain.

—Science writer Seth Mnookin, on how people have forgot what now-cured diseases were like[3]

Despite the hysteria and media coverage, the only serious medical condition ever linked to a vaccine was specific to the virus strain used in the manufacture of the vaccine. In fact, epidemiological evidence shows that vaccines prevent a huge burden of disease and death in the world.

Despite this, there is still a level of concern regarding vaccines. Public education about vaccines and health must continue, and we must continue to provide everyone with the rigorous scientific education needed so that they may avoid making vital public-health related decisions based on misconceptions and lies.

A Song Dynasty (960–1279 CE) chancellor of China, Wang Dan (957–1017 CE), lost his eldest son to smallpox and sought a means to spare the rest of his family from the disease, so he summoned physicians, wise men, and magicians from all across the empire to convene at the capital in Kaifeng and share ideas on how to cure patients of it until a man from Mt. Emei spread knowledge about inoculation.[50] The first clear and credible reference to smallpox inoculation in China comes from Wan Quan's (1499–1582 CE) Douzhen Xinfa (痘疹心法, "Philosophy on Poxes") of 1549 CE, which states that some women unexpectedly menstruate during the procedure, yet his text did not give details on techniques of inoculation.[51]

Inoculation was reportedly not widely practiced in China until the reign of the Longqing Emperor (reign 1567–1572 CE). From these accounts, it is known that the Chinese banned the practice of using smallpox material from patients who actually had the full-blown disease of Variola major (considered too dangerous); instead they used proxy material of a cotton plug inserted into the nose of a person who had already been inoculated and had only a few scabs.

Adverse reactions to the HPV vaccine Ceravix, reported between April 2008 and 23 September 2009. Very few, and fairly mild.

To put it simply: complications are more likely to arise from illness than from vaccination.

What this means is that the benefits of vaccination outweigh the risks, by far, in every case.

Most commonly used vaccines have a statistical risk of severe complications; however, the actual risk is ridiculously low. With respect to milder complications, it's often difficult to tell if the vaccine actually was the cause as the nocebo effect can be very strong with injections.

The current impact of vaccines on health is very simply stated by the CDC.[52]

Children who get measles have a 1 in 20 chance of developing a serious complication; however, serious complications from the vaccine number 1 or 2 per million, according to the Institute for Vaccine Safety at Johns Hopkins University.[53] Based on historical analysis of measles-infected vs. measles-vaccinated children, a 2015 analysis reported that it is likely that there is a long-term immuno-suppression caused by measles infection that increases the likelihood of fatality from other diseases.[54][55]

Before the introduction of measles vaccination, there were about half a million cases per year in the United States, while only 89 cases were diagnosed in 1998.[53] Historically, the mortality rate for measles in the U.S. was about 1 to 3 deaths per every 1000 cases, with young children suffering the highest mortality rates.[56] Most deaths occur as a result of pneumonia or encephalitis.[57]

After the introduction of polio vaccination, cases in the United States decreased from almost 30,000 in 1955 — many of which led to paralysis or death — to 910 cases by 1962. New cases of polio in the U.S. are now a thing of the past.[53] Of the two types of polio vaccine, the oral vaccine, while effective, is the less safe of the two. As there are no more naturally acquired cases in the U.S., the oral vaccine had become the only cause of polio (8-9 cases). Since the vaccine risk, however small, eventually exceeded the disease risk, the oral vaccine was abandoned in favor of the killed vaccine. In regions where polio is still a major problem, the oral vaccine is still a better choice, as it can enter the water supply and vaccinate others passively. In regions with high HIV rates, this may be less true, as live vaccines are usually avoided in patients with compromised immune systems.

According to Willem van Panhuis et. al. 2013, "a total of 103.1 million cases of these contagious diseases have been prevented since 1924 on the basis of median weekly prevaccine incidence rates."[58]

The US vaccine court building.

In Britain, there was concern in the early 1970s about the pertussis vaccine, where it was blamed for several cases of encephalitis. Despite the connection never being proven outright, vaccination rates still dropped from 77% to 39%. Following this drop in immunization, the UK was hit by two large whooping cough epidemics (one in 1978, and another in 1982), both of which resulted in many deaths.[53][59] Unfortunately, these sorts of consequences from vaccine denial aren't confined to history; whooping cough also hit the American northwest, generating one of the worst outbreaks in 70 years, with a 1300% increase in cases in 2012 entirely blamed on recent hysteria over vaccines.[60]

The rates of complication from vaccines are so low that the benefit of vaccines for each individual child is higher than the risk of a poor outcome, so it is not true that the few children with adverse events are being sacrificed for the health of others. Nonetheless, in the United States there is legal recognition of the potential for adverse effects from vaccines, which are handled by the Office of Special Masters of the U.S. Court of Federal Claims ("vaccine court").[61] This court uses a no-fault compensation program based on a vaccine injury table[62] that is regularly reviewed by the Institute of Medicine.[61]

On June 21, 2017 the Court of Justice of the European Union ruled that courts of the EU could consider circumstantial evidence when deciding if the vaccination of a specific individual caused a disease when there was no supporting evidence based on medical research.[63][64] The ruling would seem to be comparable to the no-fault compensation program of the US.

Incidences: Rubella occurred primarily in epidemics every 6 to 9 years. During 1964-1965, there were an estimated 12.5 million rubella cases in the United States, population approx. 191 million.[73] Rubella then affected about 0.868% of the population each year, if 12.5 million cases occurred on average every 7.5 years.

“”For generations, just about everybody in the United States got vaccinations. And as a result, diseases like measles were all but eradicated. But in 1998, a study published in a scientific journal linked vaccines with autism. Even though that study was later discredited, ever since then, a small but vocal subset of parents have refused to vaccinate their kids. Now, measles... are back! As is whooping cough, mumps, and other diseases that were nearly wiped out. Children's lives are being endangered because some parents are acting on beliefs that have no scientific evidence to support them.

Another wonderful side effect, not of vaccinations but to the opposition to them, is that when herd immunity breaks, once more or less eradicated diseases (at least in regions where vaccines were prevalent) have now been able to make a comeback. One example of this is measles, in which the cause of the return is literally the failure of people to get vaccinated due to the needless (read: needle-less) fear of vaccines.[77]

Some anti-vaxxers argue that vaccines are bad because they contain thiomersal. Usually, it is claimed that thiomersal is bad because it contains mercury. While some mercury-compounds are toxic, the concentrations of thiomersal in vaccines is so low as to be almost negligible, thiomersal's type of mercury-compound is significantly less harmful, and thiomersal has been phased out from most vaccines in developed countries.

Most vaccines contain aluminum compounds, generally aluminum hydroxide (Al(OH)3) or aluminum phosphate (AlPO4). These stimulate a more heightened immune response against the antigen in the vaccine, making it work better. Some anti-vaxxers claim that this aluminum causes autism when it is deposited in the brain, and autoimmune disorders anywhere else.[78] Though some aluminum compounds are toxic at high doses, the amount of aluminum adjuvant in any given vaccine is so low (and the amount of aluminum taken up by the brain is such a tiny fraction of that), that the risk posed by anti-vaxxers is completely overblown.[79][80][81]

A growing number of Muslims believe that Western pharmaceutical companies have intentionally tainted the polio vaccines used in their countries. They believe that Western powers secretly use the vaccines to spread AIDS and/or infertility among Muslims. An alternative story, also applied to insulin, is that the vaccine's chain of manufacture includes live pigs or pig cells. Unfortunately, this wave of hysteria has led to a sharp decrease in polio vaccinations and an almost equally sharp increase in polio cases in Muslim countries.[82] Four state governments in the predominantly-Muslim part of Nigeria further increased the hysteria by banning all polio vaccines in 2004.[83][84] This isn't limited to the developing world; Eustace Mullins wrote an article claiming the polio vaccine was a Jewish plot to mass-poison American children.[85]

An unfounded fear common to anti-abortion and anti-vaccination "activists" is that aborted fetuses are being used as ingredients in vaccines or that abortions are necessary to manufacture them. This is a distortion of the fact that the weakened form of the viruses in some vaccines are grown in a culture derived from a cell line taken from fetal tissue. There are no fetal cells in vaccines and the original fetuses were aborted way back in the 1960s.[86]

It is true that some vaccines do contain gelatin derived from pigs. Some religions object to the consumption of pig as food, most notably Judaism and Islam.[87] Both Jewish and Islamic scholars have ruled that the use of vaccines containing pig-derived products is not forbidden. In the case of the Islamic scholars, the gelatin in vaccines is considered sufficiently transformed from pig to not be of concern; in the case of a Jewish scholar, that the vaccines are not given orally was considered to be sufficient for it not to be forbidden.[87] More importantly however, most religions have particular rules, which state that in matters of life or death, nearly all laws can be broken anyway.[note 3]

“”So you've observed that some people are born with autism. Good job, that's step one. Next, you ask a question — "What caused it?". You think that it's vaccination. Now it's time to test your theory. You know that some kids who've been vaccinated develop autism, but you haven't controlled for all the other variables, such as diet, genetics, environment, chance mutations, related disabilites or simply the higher diagnosis rate due to greater awareness. Plus, you can't explain why the 99% of people who have been vaccinated didn't develop autism. OOPS! That's a shitty theory! Go back to step one!

There has been much concern about a possible link between autism and vaccines, particularly the MMR (measles, mumps, and rubella) vaccine in the UK and thimerosal in some flu vaccines.[90] Part of this concern is due to a possible rise in cases of diagnosed autism over the last few decades — much of it raised by parents of autistic children, and by prominent Americans such as Jenny McCarthy… but rarely by autistic people themselves. More often than not, evidence given by those peddling a link is indirect and anecdotal. When such groups do attempt to be scientific, they primarily cite links between ethylmercury exposure and other neurological problems outside the setting of vaccine administration. For instance, according to one source, "In 1977, a Russian study found that adults exposed to much lower concentrations of ethylmercury than those given to American children still suffered brain damage years later."[4]

The following statement, attributed to Dr Boyd Haley,[91] whom Orac has referred to as "disgraced,"[92] gives anecdotal evidence of a link between ethylmercury and "brain damage":

You couldn't even construct a study that shows thimerosal is safe... It's just too darn toxic. If you inject thimerosal into an animal, its brain will sicken. If you apply it to living tissue, the cells die. If you put it in a petri dish, the culture dies. Knowing these things, it would be shocking if one could inject it into an infant without causing damage.

This statement works to increase levels of fear, but makes no mention of actual vaccines or actual patients. It certainly doesn't mention statistics or dose levels, which is important when discussing medical effects of chemicals. Pouring a dose of a chemical into a petri-dish of cells (in vitro) is not the same as exposing an actual living human (in vivo) to the chemical — for a start the body has certain defence mechanisms against chemical attack. This is why actual studies are undertaken, and many promising anti-biotics and medicines have failed because they work in vitro but not in vivo.

Several very well-done population-based studies have been conducted into the link between autism and vaccinations, although they aren't very widely reported. These hard facts tend not to resonate with the public consciousness and media as much as anecdotes and sob stories from concerned individuals and interest groups do. This has been a problem with health scares for decades, and shows no sign of going away. The particular studies have looked at actual populations in real life conditions, exposed to the actual substance in question; none have shown any connection between autism and the thimerosal preservative or the MMR vaccine. There is overwhelming evidence that the MMR and thimerosal-containing vaccines play no role in the development of autism.[93][94][95][96][97][98][99][100] This contrasts with many of the papers supposedly showing a link, which are often underpowered or badly controlled. Ironically, one epidemiological study has indicated the MMR vaccine has reduced rates of one risk factor for autism-congenital rubella syndrome.[101]

A small study by Andrew Wakefield, published in The Lancet in 1998, became infamous around 2000-2002 when the UK media caught hold of it. It hypothesized an alleged link between the measles vaccine and autism despite a small sample size of only 12 children. This eventually led to what Guardian columnist and science writerBen Goldacre described as "the media's MMR hoax,"[102] due to the evidence for any link being so lacking that it may as well have been entirely manufactured. The paper was partially retracted several years later but continued to be the most often cited case study for the link, despite mounting evidence (including one large study into the rates of autism in adults who wouldn't have received MMR) to the contrary. It was finally considered "thrown out" on February 2, 2010 after it was discovered that Wakefield behaved unethically. Specifically, he was found guilty of not acting in the best medical interests of the children he did research on (one child was severely injured in a colonoscopy), as well as not disclosing his previous involvements with anti-vaccination groups prior to the study and it hitting the news.[103] Further examinations show that Wakefield outright fabricated information or selectively ignored facts in his study, such as preexisting conditions in 5 of the 12 children.[104]

Additionally, the CDC has been accused by anti-vaxxers, including Wakefield, of covering evidence for years on a study in 2004 that otherwise shows no evidence between vaccination and autism. There is, however, apparently omitted data that allegedly shows MMR vaccination rates being correlated with autism diagnosis in a small subset of male African American infants. In reality, the "whistleblower" William W. Thompson and his traitor friend Brian Hooker are sympathetic to the anti-vaccine movement. Thompson has an axe to grind for the CDC while Hooker is full-on anti-vaxxer, and he has secretly recorded phone calls with Thompson and edited the footage. Hooker attempted terrible epidemiology (he has no background in it nor did he consult a statistician for help) for a "reanalysis" for the study that had results he didn't like. Those results were published in a journal with practically zero impact, and even that was redacted for questionable statistical methods and undisclosed conflicts of interest.

Autistic adults and other reasonable-minded people maintain that it is hate speech to claim that vaccines cause autism because it implies claiming ipso facto that a person is better off dead of an easily preventable disease than alive and autistic.[105][106] Anti vaxxers have also been accused of hating autistic children due to comments made by anti vaxxers characterizing autistic children as brain-damaged[107] and soulless.[108] It doesn't help when they make outright statements that the deathes of children are acceptable collateral damage in furtherance of the spread of her message[109]

Concern has been raised about a connection between MS and vaccines, especially the Hepatitis B vaccine. One of the several studies done on the topic showed a potential link,[110] but there were methodological problems,[111] and most other studies failed to show a link.[112][113] The most recent CDC publication on the matter cites fifteen different studies showing no link between MS and the Hepatitis B vaccine.[114]

The DTaP vaccine has been suspected of causing Sudden Infant Death Syndrome, which causes children to stop breathing and die.[115] However, studies have not shown a connection between SIDS and DTaP vaccinations.[116]

Recent studies have identified abnormalities in the development and function of medullary serotonin (5-HT) pathways in the postmortem brain from sudden infant death syndrome (SIDS) cases, suggesting 5-HT-mediated dysregulation of the autonomic nervous system in SIDS.[117][118] This is basically stating that SIDS has a strong genetic component and is more prevalent in families that have issues with serotonin re-uptake, thus preventing the infant from shifting when their airway becomes blocked while asleep.

Research into SIDS is progressing, and has left behind the fictional link to vaccines.

"Vaccinosis" or "Chronic Vaccine Disease" is a term invented by the alternative medicine fraternity to describe a raft of symptoms purportedly caused by vaccines. Like many made-up illnesses, claims about "vaccinosis" often exploit genuine symptoms, such as known adverse reactions to vaccines, and exaggerate them to pander to fear and mistrust of medicine.[122]

According to The Free Dictionary, the definition of vaccinosis is, "Chronic illness, discomfort, or malaise that results from immunization."[123] In contrast, the WHO defines vaccinosis as: "Your search for vaccinosis did not match any documents."[124] The CDC, on the other hand, defines vaccinosis as "No pages or documents were found containing 'vaccinosis'."[125]

Under-vaccination and delayed vaccination of children is a much more common problem than completely unvaccinated children. "Overwhelming their developing immune systems" is frequently given as an excuse for parents to delay or skip some vaccines for their children.[126][127]

Because the number and frequency of childhood vaccines has increased over the years[note 4] and because many parents have never seen the horrible effects of most of these separate childhood diseases[note 5], an increasing number of parents have become vaccination-shy on behalf of their children.

A review of medical literature concluded:

“”Current studies do not support the hypothesis that multiple vaccines overwhelm, weaken, or "use up" the immune system. On the contrary, young infants have an enormous capacity to respond to multiple vaccines, as well as to the many other challenges present in the environment. By providing protection against a number of bacterial and viral pathogens, vaccines prevent the "weakening" of the immune system and consequent secondary bacterial infections occasionally caused by natural infection.

One claim, promoted widely across the internet, holds that CDC research showed that breastfeeding reduced the effectiveness of vaccines, and so breastfeeding should be stopped or postponed.[129][130][131][132][133][134] However, the study made no such conclusions.[135]

Vaccines are often touted as a major source of revenue for Big Pharma (the pharmaceutical industry). However, vaccines have much lower profit margins than alternative drugs and only make up 2-3% percent of a trillion-dollar worldwide pharmaceutical industry.[136]

For example, Hepatitis A, B and C all currently infect over 100 million people. Vaccines are available for Hepatitis A and B, but not Hep C. Sovaldi, a drug used to cure Hep C is available, at a list price of $84,000 in America[137]. Medicare alone paid over $3B for Sovaldi in 2014,[138] and a grand total of $7.8 Billion in the US for just this one drug,[139] not including Harvoni and older drugs still in use for Hepatitis C. In 2014, the total spending on all vaccines other than flu was $6.9 billion.

If pharmaceutical companies only cared about the bottom line, they wouldn't manufacture vaccines at all.

Some ideologues oppose vaccination for political or moral reasons. For example, certain conservatives oppose the use of Gardasil on young girls for fear that it will discourage them from sexual abstinence by eliminating an STD,[140][141] thereby depriving the right of one of its favorite pro-abstinence scare tactics. Bear in mind that these are the same people who claim to be "Pro-Life", opposing a vaccine that's known to save lives by preventing cervical cancer. Though it won't placate Christian fundamentalists from promoting ineffective abstinence-only sex education programs, the CDC announced that a study has shown that Gardasil does not increase the likelihood of unsafe sex among teens.[142]

A measles outbreak centered round a megachurch that the family of Texasfaith healer and televangelistKenneth Copeland runs. Church officials denied that they oppose medicine or vaccination. Still people who know the culture of the ministry claim a general sense that believers should rely on God rather than modern medicine to stay well. “To get a vaccine would have been viewed by me and my friends and my peers as an act of fear — that you doubted God would keep you safe. . . . We simply didn’t do it.” Former church member Amy Arden stated.[143]

Another example was when strange congressman Louie Gohmert voiced his equally strange concerns about vaccination on a Family Research Council broadcast: he's convinced that liberal elites are using vaccination programs to cull the earth's human population due to concerns about the scarcity of natural resources. Apparently, the evil cabal behind such a plan are aiming for a target population of 700 million, which indicates that Gohmert may have pulled that number out of his ass arrived at that number by purely imaginary means.[144] It's also backwards, of course, since vaccines save lives, and even anti-vaxxers don't claim that they kill people.

Libertarians also oppose mandatory vaccination, believing simply that the state does not own your body, and therefore mandatory vaccines are a direct contradiction to individual liberties.[145] (Note that vaccination is most effective when everyone else is also vaccinated, meaning this is a clear case of individual choices affecting the "liberty" of others.) So-called Beltway libertarians among others usually make an exception for state-mandated vaccination out of practicality, much as they do national defense. Ronald Bailey at Reason has covered the issue[146] with an argument part moral and part pragmatic, which looks something like this:

(2) Vaccines considerably reduce the likelihood that the vaccinee will contract the disease being vaccinated for.

Corollary: Taking vaccination as a baseline (which, in the developed world, it is), the unvaccinated are more likely to contract diseases for which vaccines are in widespread use than the average person.

(3) You are more likely to catch many of these diseases from someone who has contracted the disease than from someone who has not.

(4) Per (3), the more people around you have a given contagious disease, the more likely you are to contract it.

Corollary: People around you are more likely to contract said disease if you have it.

(5) Per (2), (3) and (4), the more people around you are vaccinated, the less likely you are to contract the disease for which they are vaccinated.

This is the case irrespective of whether you personally are vaccinated or not.

Corollary: If you personally are vaccinated you are less likely to contract that disease, and therefore less likely to transmit it to people around you.

Corollary of corollary: If you personally are unvaccinated you are more likely to contract the given disease, and therefore more likely to risk transmitting it to people around you.

In both directions, this is the basis of herd immunity: every individual vaccinee in a population reduces the likelihood that a case of a disease will occur at all, and every case that doesn't occur reduces the likelihood, in the rare cases where a vaccine does not work as expected for a given individual, that the individual will ever be exposed to the pathogen anyway. The success of mass smallpox vaccination illustrates the positive feedback loop at work here.

(7) As a consequence of the various parts of (6) and the corollary established in (2), by abstaining from vaccination the abstainer exposes people around him to a risk of disease greater than the baseline.

(8) Per (7), abstention from vaccination may be reasonably perceived as endangering people around you.

“”Can you explain why better nutrition and sanitation eliminated polio in 1954-55 but waited until 1964 for measles? It's very sneaky of nutrition and sanitation to kick in only at the same year vaccines are released.

Many anti-vaxxers claim that better sanitation is the true reason that rates of diseases were massively reduced around the time. This is very questionable. As noted by the quote above, not all diseases decreased at the same time or the same rate, suggesting that they were not prevented by the same changes. "Sanitation" is not a binary -- for example, modern toilets and plumbing, which hugely helps in preventing waterborne diseases such as cholera, took many decades to reach even a majority of citizens in any country. And polio has been nearly eradicated not by eliminating world poverty and lack of sanitation, but via vaccination -- so even if sanitation helps, it is clear that vaccines work.

Some anti-vaxxers, rather than holding some truly far-fetched idea about autism or other diseases being caused by vaccines, claim that natural infection is better for a child than vaccination, simply because it is natural. Very few of these same people want to give their kids large doses of all-natural cyanide, though, for reasons unexplained. That aside, there are several problems with this approach:

Vaccines have a much smaller likelihood of causing the symptoms of the disease, such as pneumonia (pneumococcus et al.), meningitis (Haemophilus influenzae, type b), liver cancer (hepatitis B), etc.

Some vaccines do a better job building immunity than a "normal" infection with the corresponding disease.[149] It is known that measles infection causes short-term immuno-suppression, and there is evidence to believe that it also causes long-term immuno-suppression.[54][55]

Many of the alleged means by which to infect your child are either hit-and-miss or outright scams.

“”Disease is pestilence, and pestilence is from the Devil. The devil is germs and disease, which is cancer and any of those things that can take you down. But if you trust in the Lord, these things cannot come near you.

In August 2013, there was an outbreak of measles in the Eagle Mountain International Church based in Newark, Texas. The pastor, Terri Pearsons, was critical of vaccines (due to the mythical autism link) and because of this the majority of the church's members refused vaccination. After a member of the congregation traveled to Indonesia they brought the measles back, where it spread quickly to the congregation, staff, and day care. Every reported case (21 total in the church) came from people who refused vaccination. There were no deaths from the outbreak, and the silver-lining came in the form of Pearsons reversing stance and advocating vaccinations, as well as the church hosting vaccination clinics. [151] Another outbreak in late 2014-early 2015, which started in Disneyland, was directly linked to children who weren't vaccinated, where 15 of the original 20 patients in the outbreak had not received the MMR vaccine.[152]

In the United States it is generally held (perhaps "legally held" is a better way to phrase it) that parents have the right to have their children not be inoculated if they, the parents, so desire.

The H1N1 swine flu vaccine was a hot topic among vaccine denialists, from fears the vaccine was unsafe (stoked by reports of side effects from the old 1976 swine flu vaccine) to conspiracy theories that the vaccine was a plot to curb overpopulation.[153]

Safety concerns about the HPV vaccine Cervarix were raised after a girl died after being injected with the vaccine.[154] The story was immediately jumped on by anti-vaccination groups and was widely reported in the general and scaremongering media. It was later determined that the death was due to an undiagnosed tumour, but the same media that cried out for "more research" into the incident preferred to bury this conclusion; undoubtedly a large part of the UK population still believe the young girl died due to a direct reaction to the vaccine. Anti-vaccination blogs and organizations, of course, have cried foul on this conclusion. The Sunday Express also hyped up fears about the jab by — one can only assume deliberately — misquoting Dr Diane Harper and claiming that the vaccine was "just as deadly as the cancer." Indeed, practically every single one of the claims, which were on the front page of the newspaper, were false; ranging from what Dr Harper actually said, to her actual level of involvement in the vaccine. In true tabloid style, the corrections were well and truly buried.[155]

In April 2015, California legislators proposed removing the "personal belief" exemption from childhood vaccination requirements in public schools.[159] The proposed legislation does not remove a religious exemption, so how "personal belief" can be differentiated from religion remains to be seen[6][7] if the legislation passes in this form. Discredited ex-doctor Andrew Wakefield has begun rallying the antivax troops against this proposed legislation. He is reportedly contemplating busing chiropractic students to rally at the state capitol.[160] The final bill that was signed into law by Governor Jerry Brown removed both the personal and religious exemptions from vaccine requirements.[161] The ending of the personal/religious belief exemptions has resulted in overall higher rates of immunization (the exemption rate dropped from 2.54% to 1.06% from 2015 to 2016), but the medical exemption rate rose from 0.17% to 0.51% during the same period.[162]

Having lost the legislative fight in California, antivax activists are attempting to recall state Senator Richard Pan from office. Dr. Pan, a pediatrician, was the primary author of the mandatory vaccination legislation.[163] The activists are also attempting to get an initiative on the state ballot that would overturn the legislation.[163]

In 2016, Leontine Robinson lost a lawsuit against her former employer, Children’s Hospital in Boston. Ms. Robinson worked near children at risk at the hospital, and she had refused to get a flu shot because she is a member of the Nation of Islam, and some flu shots contain a pig-derived gelatin, which she claimed was prohibited by her religion.[87] Ms. Robinson was given an opportunity to find another position at the hospital that was not near children but was unable to do so; she subsequently sued her employer after her employment was terminated. The judge in the case ruled against Ms. Robinson, stating, "Had the Hospital permitted her to forgo the vaccine but keep her patient-care job, the Hospital could have put the health of vulnerable patients at risk."[164]

In 2017, Mark Blaxill of the crank Age of Autism and chair of Health Choice propagandized the Somali-American community during a measles outbreak in Minnesota about what he alleged was a vaccine-autism link.[165] Some Minnesotan responsible health care workers have fought back against the propaganda.[165] Minnesota's worst measles outbreak in decades has emboldened rather than cowed the antivax movement and they have recruited associates of Andrew Wakefield to the state.[166]

A 2012 survey of US pediatricians and family physicians that was published in 2015 reported that one-fifth of pediatricians refused to treat children of vaccine refusers, primarily to protect other patients.[167][168]

More recently, the MMR-autism link (mentioned above) hit the UK headlines after Andrew Wakefield, the lead author of a paper suggesting a link between autism and MMR, was found guilty of unethical conduct. Despite the ruling only applying to his ethical conduct in the research, which had been questioned for several years (a "conflict of interest" was raised in 2004, three years after he left the Royal Free Hospital under controversial circumstances), the UK media have taken the ruling to also mean "his work has been discredited."[169] As those who may have seen Wakefield's original research would know, a series of 12 case studies never particularly had any credit to actually be discredited,[170] and Wakefield's conclusions had been repeatedly discounted by further study long before the ethical matters were ruled upon. The Lancet — the premier medical journal that featured his research — issued a full retraction of the study in February 2010.[171]

In August 2010, the Finnish National Institute of Health and Welfare recommended that use of the Pandemrix H1N1 vaccine should be discontinued, pending investigation into 15 cases of narcolepsy in recently vaccinated children and adolescents in the previous year.[172] At the same time, the European Medicines Agency and the Swedish Medical Products agency launched their own investigations to the vaccine. Far from being quashed by Big Pharma, these studies were completed in early 2011, and concluded that there was indeed an increased relative risk of developing narcolepsy in children and adolescents vaccinated with Pandemrix. A number of follow-up studies have found various relative risks, ranging from about 3 [173] to as much as 7.5.[174] Because narcolepsy is so rare to begin with, relative risks are hard to estimate, and the confidence intervals mentioned in the studies reflect this, generally giving a range of half to one and a half times the cited risk. Also because of the rarity, the actual risk amounted to some four additional cases per 100 000 people per year.[173]

As is usual with stopped clock cases, these findings did not result in widespread paradigm shift against vaccinations in medicine. Instead, the scientific method labored on to produce a model that explains these findings. A research group suggested that narcolepsy might be caused by the fact that certain surface proteins of the H1N1 virus resemble hypocretin, a neurotransmitter that transmits the "wake up" signal.[175] In June 2014, they retracted the paper after having failed to reproduce its key findings, although they continue to believe that their original hypothesis remains valid.[176] Later in the same year, a research paper comparing Pandemrix with another vaccine with the same adjuvants but different viral antigens concluded that the focus for finding the cause should be the viral antigens and not the vaccine adjuvants.[177]

In 2015, Pakistan arrested about 500 parents for refusing to have their children vaccinated against polio, and over 1000 arrest warrants were issued. Officials turned to these drastic means because of community stupidity opposition and Taliban threats. Sixty-four workers from polio eradication teams have been killed for doing their work since 2012.[178][179] In 2014, Pakistan had the highest number of new polio cases in the world: 327 of 413 total (or 306 of 359 of wild-derived cases).[180]

In 2015, Pakistan and Afghanistan became the last two countries with endemic polio. In November 2015, a local polio coordinator was assassinated in the northwestern Swabi district. On January 13, 2016, a suicide bomber killed 15 people in the vicinity of a vaccination clinic in Quetta.[181]

Australia cut welfare payments to parents of unvaccinated children starting in 2016.[182] In response, many parents got their children's vaccinations up to date.[183] Anti-vaxxers, in the meantime, started setting up "black market" childcare facilities.[184] The predictable happened as early as 2015, when eighty children caught chickenpox in one such facility.[185]

In recent years, the anti-vaccination movement gained so much traction and diffusion in Italy that vaccination rates lowered below safety levels. The antivax people in Italy often sport radical political views, causing the debate to become highly polarized. In the course of 2016-2017, many things happened at once: an epidemic of measles, another epidemic of meningitis, a child was infected by tetanus (after many years of absence), and so on. The scientific community answered by increasing the level of discussion on vaccines, trying to better inform the public (especially notable is the work of some of the best Italian doctors, such as Roberto Burioni). Moreover, these facts prompted the government to take some steps against antivax doctors (a couple of them were expelled by the medical college), and to raise the number of mandatory vaccines from 6 to 12. The new law is still being discussed by the parliament, as of June 2017.

In 2018, a coalition of right-wing (Lega Nord) and left-wing (Five Star Movement) populist parties formed a coalition government. Both parties have opposed the mandatory vaccination law, and in August 2018 the parliament overturned the 2017 law that mandated vaccination.[186] The repeal has occurred at a time when Italy has the second highest measles rate in Europe after Romania.[186] The rise in anti-vaccinationism in Italy has been attributed to Wakefield's discredited autism study, but has been fueled by a 2012 Italian court ruling that MMR caused autism (the ruling was subsequently overturned in 2015).[186][187]

In France, certain vaccinations are made mandatory by 2018.[188] Despite this, it's by far the place where anti-vaxxers exert the largest amount of influence. A study found out that 40% of people in France judge vaccination as an unsafe medical procedure.[189]

After the fall of the Soviet Union, Russia has experienced a serious decline in vaccination rates;[190] as of 2017, 48.7 percent of Russian children born in 2016 had not been vaccinated on schedule. The most common excuse to not vaccinate children is "personal choice" and doubt the efficacy of vaccines, as well as being distrustful of authority. Parents can simply say that they don't want their kids vaccinated, far easier to get personal belief exemptions than on the U.S. Homoepathy remains to be a popular "alternate" choice to vaccinations. Anti-vaccination runs to the point where even some doctors have doubts about vaccines, though scientific consensus remains that exemptions are unnecessary. Unsurprisingly, outbreaks of measles have become far more common, with 1,717 measles cases between January and June of 2018 compared to 127 cases in January-June of 2017, a 13.5 fold increase.[191]

There has reportedly been an increase in resistance from anti-vaxxers to vaccinating dogs and cats.[192][193] This is apparently at least partly due to pet owners' erroneous fears that their pets will get autism, even though autism has never even been studied or diagnosed in non-humans, even if autism is applicable in the first place.[193]

Common practices to encourage more parents to have their children vaccinated have been ineffective.[194] These ineffective practices are included here:[194][195]

Explaining that there is a lack of evidence showing that vaccination causes autism

Explaining the dangers of diseases prevented by vaccination

Showing images of children with diseases that could have been prevented by vaccination

Explaining that diseases could kill but are preventable from vaccination

Explaining herd immunity

In response to this, researchers conducted two independent surveys using "moral foundations theory" from psychology.[196][195] Moral foundations theory attempts to place people on five or six scales of morality (care-harm, fairness-cheating, loyalty-betrayal, authority-subversion, purity-degradation, and liberty-oppression) to understand how they come to moral decisions.[195] The results of the research found that while messaging that encouraged vaccination focused on the harm and fairness parts of the scales, "vaccine hesitancy" parents (potential anti-vaxxers) instead fell on the purity and liberty parts of the scales.[196][194] The researchers concluded that there is a "need for inclusion of broader themes in vaccine discussions,"[196] but which messaging is effective on reducing vaccine hesitancy still needs to be tested.[195]

↑"The Cow-Pock—or—the Wonderful Effects of the New Inoculation!—vide. the Publications of ye Anti-Vaccine Society": 1802 engraving by James Gillray

↑In his own words: "What I've read about what they think I'm saying is not what I've said. I'm not a germ theory denier. I believe vaccinations can work. Polio is a good example. Do I think in certain situations that inoculating Third World children against malaria or diphtheria, or whatever, is right? Of course. In a situation like that, the benefits outweigh costs. But to me living in Los Angeles? To get a flu shot? No."

↑"Vaccination Exemptions," The College of Physicians of Philadelphia, undated, accessed February 8, 2013; "Exemptions from providing medical care for sick children," Children's Healthcare is a Legal Duty.

↑Which was in turn credited as taught by deities from the mountain. Needham, Joseph. (2000). Science and Civilization in China: Volume 6, Biology and Biological Technology, Part 6, Medicine. Cambridge: Cambridge University Press. p.154T